Rotary engines



Allg- 29, 1957 A. F. AAAAAA 1 1. 3,338,220

ROTARY ENGINES I 2O Y ,C

ac FRA/VK MARSHALL Aug 29, 1967 A. F. MARSHALL 3,338,220 A i ROTARY ENGINES Filed Qot. 5, 1964 3 sheets-sheet s FIGA 34 mfc FRANK MARSHALL United States Patent O 3,338,220 ROTARY ENGINES Alec Frank Marshall, Dorridge, Solihull, England, assignor to The Birmingham Small Arms Company Limited, Birmingham, England, a British company Filed Oct. 5, 1964, Ser. No. 401,388 Claims priority, application Great Britain, Oct. 4, 1963,

39,100/ 63 3 Claims. (Cl. 123-8) This invention relates to rotary engines of the kind in which a rotor or rotating piston rotates and oscillates on a predetermined orbit within a suitably shaped stator. In one known form, a substantially triangular rotor so turns within a two lobed epitrochoidal shaped stator. In other forms either the rotor or stator may be, or approximate to either epitrochoids or hypotrochoids with the relationship of stator lobes to rotor sides of n+1 and n-l respectively.

An object of the present invention is to provide in a rotary engine of the kind referred to, means of controlling the rotation and oscillation of the rotor within the stator without recourse to a combination of gear and bearing systems.

According to the main feature of this invention a rotary engine of the kind referred to, has a bearing system for the rotor wherein the inner surface of the rotor is so formedy and adapted to co-operate with a suitably shaped stationary inner member insuch a manner as to constitute or approximate to an epitrochoidal or hypotrochoidal rotary system of the n+1 or n-l type.

According to a further feature of the invention, a power take oif is provided by hydraulic or pneumatic means, by one or more pumping chambers directly driven by the rotor without the use of any intermediate gear or friction drive.

The use of such hydraulic or 'pneumatic means of power take oi may be arranged so that the load on the bearing system during a power pulse from the rotary piston is partially balanced.

Such methods of power take ot are particularly applicable to motor vehicles and facilitate the use of cheap, gearless type of transmission.

A further feature of the invention comprises a rotary engine of the above characteristics but in which two pairs each consisting of a compression and an expansion variable volume chamber are used so that power is transmitted from one such pair of chambers during the compression stroke of the complementary pair of chambers, and vice versa.

The sets of the variable volume chambers on the driven section of the invention may be used to provide hydraulic and pneumatic power such that hydraulic power is available for main propulsion purposes and pneumatic power available for engine supercharging, pneumatic auxiliary actuation, and the supply of secondary air to an afterburner.

Two embodiments of the invention will now be described by way of exempliiication with reference to the accompanying drawings in which FIG. 1 is a cross-sectional view taken along line -B-B on FIG. 2 of a rotary engine having a three lobed engine rotor which has a four lobed inner surface which bears on a three sided inner member.

FIG. 2 is a cross-sectional view taken along line A-A on FIG. l.

FIG. 3 is a cross-sectional View of a rotary-engine having a four lobed engine stator and a ve sided rotor which has a live lobed inner surface which bears Von a four sided inner member.

FIG. 4 is a cross-sectional View taken along line C-C on FIG. 3 and 3,338,220 Patented Aug. 29, 1967 ICC FIG. 5 is a partial view of the cross-sectional view shown in FIG. 4 illustrating an alternative construction.

Referring to FIGS. 1 and 2, the engine comprises a stator 1 in which a rotor`2 orbits. The stator is constructed with an inlet port 3, an exhaust port 4, and a recess for a sparking plug 5.

Attached to the rotor 2 are pump rotors 6 and 7. These pump rotors orbit with the rotor 2 inside pump stators 8 and 9. The pump stators are also constructed with inlet ports 10 and outlet ports 11. Side plates 12 and 13 are arranged adjacent to the pump stators and the side plates 12 and 13, the pump stators 8 and 9, and the engine stator 1 are all clamped together by means of nuts and bolts 14. The combined engine rotor 2 and pump rotors 6 and 7 have a four lobed internal surface 15 which is adapted to co-operate with a threev sided stationary spindle 16 to produce the required orbit of the rotors. 'Ihe spindle 16 is also clamped between the side plates 2 and 3 by means of nuts 17.

The engine operates on the conventional four stroke cycle, drawing a mixture of air and fuel in through the inlet port 3, comprising the mixture, igniting it -by means of a sparking plug, and after expansion of the burning gases exhausting the burnt gases through the exhaust port 4. Four tiring impulses per one revolution of the rotor are obtained.

The pump rotors 6 and 7 are of similar geometric shape to the engine rotor 2 and are employed as uid pumps in which, as the pump rotors turn (in ya clockwise direction in FIG. 2), suction and then delivery of a duid which may be compressible, is made |by uncovering, and later sealing the ports 10 and 11. Suction and delivery valves (not shown) may be used to control the liow of iluid Ibeing pumped. An additional inlet port 18 'and an outlet port 19 is provided in the engine stator 1 so that the engine rotor 2 is utilised to` supplement the pump rotors. A substantial balancing of the torque reaction of the expanding gases in the firing section of the engine is also achieved by this arrangement and the loads on the rotor bearings are also reduced.

In operation the engine rotor 2 and the pump rotors 6 and 7 orbit in fixed relation about stationary three sided spindle 16 within the chamber of stator 1.

The rotary engine illustrated in FIGS. 3 and 4 cornpriscs a stator 20 and a tive sided rotor 21. The -rotor has a live internal shape 22 which is adapted to co-operate with a four sided spindle 23. The -rotor rotates in an anticlockwise direction in FIG. 3. Inlet ports 24 and exhaust ports 25 ar'e provided in the walls 26 and 27 of the stator, and two sparking plugs (not shown) are provided, at points 28 and 29 in the stator 20.

Side plates 30 and 31 are arranged adjacent to the walls 26 and 27 of the stator, and the whole assembly is clamped together by means of nuts and bolts 32, Iand spindle nuts 33. Incorporated in lthe side plates are couplings 34 adapted to be connected to -carburettors and/or exhaust pipes.

This engine also operates on the four-stroke cycle, there being ten tiring impulses per one revolution of the rotor` Means for taking power from lthe engine comprises utilising the rotor bearing system as a pump.

Inlet, 35 and outlet, v36 ports are provided in the walls 26 and 27 of the stator leading to the bearing system. Thus as the rotor 21 turns the inlet and outlet ports are successively covered and uncovered and the variable volurne around the spindle 23 causes iluid to be pumped through the ports.

In a modilication, FIG. 5, the stator walls 26 and 27 Iand the stator 20 are clamped together Iby means of threaded rings 37 and 38 engaging screw threads on the stator.

3 The walls 26 and 27 are tapered and are adapted to be clamped by tapered portions on the rings.

The bearings of the rotors, such as the spindles and the internal forms of the rotors (inserts in the rotors having the required epitrochoid or hypotrochoid forms may ibe provided) are preferably made by the powder metal art.

It is also envisaged that both systems for power take off may be employed in reverse -for starting the engine using a uid power reservoir, or separate uid source power, or electrical power source incorporating such controls in particular of frequency, as are required to operate the generator previously ldescribed `as on asychronous mot-or.

It may also be desirable to arrange the driving rotor and casing angularly displaced in relation to their corresponding sections on the bearing rotor and centre. Similarly .the pump rotor and casing may be angularly displaced with respect to the bearing rotor and casing.

I claim:

1. A rotary internal combustion engine comprising Va stator enclosing an internal chamber, means in the stator defining fuel inlet and exhaust ports for said chamber, a

rotor mounted for rotation in a predetermined orbit within said chamber, said .rotor having a through inner lobed peripheral surface and an outer peripheral surface cooperatively engaging and moving around the inner surface of said stator during operation of the engine, means for supporting and guiding said rotor in its orbit compris'- ing a stationary inner member xed with respect tosaid stator extending through said rotor having an outer lobed peripheral surface in bearing engagement with said rotor inner surface, said engaged inner member and rotor surfaces conforming substantially to an epitrochoridal or hypotrochoidal rotary system of the n and n+1 lobed type and power `output means operatively connected to said rotor to be driven thereby, said stationary inner member being the only part that engages a -radially inwardly directed surface of said rotor for providing an outwardly directed bearing support for said rotor.

2. A rotary 'internal combustion engine comprising a stator enclosing an internal engine chamber land pump chambers at opposite sides of said engine chamber, means in the stator defining fuel intake and exhaust ports for said engine chamber and inlet and outlet por-ts for said pump chambers, an engine rotor mounted for rotation in a predetermined orbit in said engine chamber, pump rotors mounted in fixed relation to opposite sides of said engine rotor and disposed in said pump chambers, said pump rotors :being -of similar geometric shapelto said engine rotor and said pump chambers being of similar geometric shape to said engine chamber, means defining a lobed inner surface extending through said pump andY engine rotors, and means for supporting and guiding said pump and engine rotors comprising a stationary lobed inner member extending through said pump and engine rotors in bearing engagement with said rotor inner surface, said inner member and asid rotor inner surface conforming substantially to an epitrochoidal or hypotrochoidal rotary system of n and n+1 lobe type.

3. A rotary internal combustion engine as recited in claim 2, comprising further inlet and outlet ports in the stator leading to said engine chamber in spaced relation to said fuel intake and exhaust ports, whereby said engine rotor is utilised `as ya iuid pump and also permits a substantial degree of balancing of the torque reaction of the expanding gases in the firing section of the engine.

References Cited Y UNITED STATES PATENTS 1,3 89,189 8/ 1921 Pruerheerd 123-8 2,993,482 7/ 1961 Froede 12S- .8 3,062,435 11/ 1962 Bentele 123-8 3,108,578 10/ 1963 Scherenberg 123-8 3,242,912 3/1966 Huber 123-8 FOREIGN PATENTS 679,411 2/ 1964 Canada. 1,328,929 4/ 1963 France.

939,015 10/ 1963 Great Britain.

ORIS L RADER, Primary Examiner.

G. SIMMONS, Assistant Examiner. 

1. A ROTARY INTERNAL COMBUSTION ENGINE COMPRISING A STATOR ENCLOSING AN INTERNAL CHAMBER, MEANS IN THE STATOR DEFINING FUEL INLET AND EXHAUST PORTS OF SAID CHAMBER, A ROTOR MOUNTED FOR ROTATION IN A PREDETERMINED ORBIT WITHIN SAID CHAMBER, SAID ROTOR HAVING A THROUGH INNER LOBED PERIPHERAL SURFACE AND AN OUTER PERIPHERAL SURFACE COOPERATIVELY ENGAGING AND MOVING AROUND THE INNER SURFACE OF SAID STATOR DURING OPERATION OF THE ENGINE, MEANS FOR SUPPORTING AND GUIDING SAID ROTOR IN ITS ORBIT COMPRISING A STATIONARY INNER MEMBER FIXED WITH RESPECT TO SAID STATOR EXTENDING THROUGH SAID ROTOR HAVING AN OUTER LOBED PERIPHERAL SURFACE IN BEARING ENGAGEMENT WITH SAID ROTOR INNER SURFACE, SAID ENGAGED INNER MEMBER AND ROTOR SURFACES CONFORMING SUBSTANTIALLY TO AN EPITROCHORIDAL OR HYPOTROCHOIDAL ROTARY SYSTEM OF THE N AND N+1 LOBED TYPE AND POWER OUTPUT MEANS OPERATIVELY CONNECTED TO SAID ROTOR TO BE DRIVEN THEREBY, SAID STATIONARY INNER MEMBER BEING THE ONLY PART THAT ENGAGES A RADIALLY INWARDLY DIRECTED SURFACE OF SAID ROTOR FOR PROVIDING AN OUTWARDLY DIRECTED BEARING SUPPORT FOR SAID ROTOR. 